Electric zinc-furnace with integral condenser.



J. THOMSON.

ELECTRIC ZINC FURNACE WITH INTEGRAL CONDENSER.

APPLIGATIONFILED APR.14,1913.

Patented Feb. 10, 1914.

2 BHEETSSHEET 1.

WITNESSES 'P/y @LMW,

INVENTOR A Mi ATTORNEYS J. THOMSON.

- ELECTRIC ZINC FURNACE WITH INTEGRAL CONDENSER.

APPLICATION FILED APR.14, 1913.

Patented Feb. 10, 1914.

WITNESSES QN k z 3N I 4 R MN\ I\\\.N Q fln M 2% i w, I W m N m u m u l m\w m w QN/H/ xx m m kw m m u h m, 4 ww u n u S m m N u m m u m m u m u nu a M n N u u JOHN THOMSON, OF NEW YORK, N. Y.

I ELECTRIC ZINC-FURNACE WITH INTEGRAL CONDENSER.

Specification of Letters Patent.

Patented Feb. 10, 1914.

Application filed April 14, 1913. Serial No. 760,916.

vofzinc having for its object the production of zinc fume which issubsequently condensed to liq uld metal.

A description of the particular means for attaining the desired resultsand such an elucidation of the general principles applicable thereto aswill provide a complete disclosure of the invention will beconcurrentlypointed out in connection with the description of theaccompanying drawings; which. represent certain embodiments of theinvention Figure'1 is a transverse .center section, as on the line A ofFig. 2, viewed in either di rectiong-Fig. 2, from the left hand side tothe longitudinal center line, B, is a onefourth top plan view while theright hand portioniis a horizontal section taken onthe plane denoted byC in Fig. 1, and Fig.- 3 is a detached detail modification of a portionofthe condenser.

This furnace is parti ularly intended for the reduction of any sul d oroxidized zinc,

- or lead-zinc, ores having a considerable content of gangue which iscapable of being transformed or dissolved into a liquid slag or matte. I

To avoid explanatory statements which would in fact be in the nature ofrepetitions, it isprefatorially set forth that this applicat-ion'is moreor less correlated with several of the previous applications filed bythe present applicant on January 2d, 1913; but reference may beparticularly cited to Serial No. 7 39,7 95 thereof. Thisapplication isalso related to another application (Case 5}, Serial No. 7 60,915, filedconcurrently herewith. Y

The decomposition of the charge is effected by heat derived by directconduction or radiation, or by both, from compound porousbed-resistors,such as are ordinarily formed from pieces of broken carbon inter polatedbetween terminals. A portion in horizontal pl one of such resistors isdenoted in the drawings, as D, with a pair of terminals, as 3, 4:,connected to the power circuit, as E. The resistors may be energizedseparately, in parallel or in series. The reaction takes place at orcontiguous to one of each of the vertical. fatesof each resistor; whichmay be somewhatrectangular in cross-section, the lower narrow sideresting upon a re fractory grating preferably built from spaced rods orbars, as 5, supported by ledges 6, above slag-sumps 7, 7. But theaforesaid grating, or hearth, may be formed of pierced or perforatedbricks, slabs or tiles. Each resistor lies parallel to the other andthey are sufliciently separated to provide space for a charging gallery,F, between them, preferably located in the center of the furnace. Thegallery, or space between the o posing vertical faces of the resistorsmay e sub-divided by a series of longitudinal center plates, as 8, andtransverse plates, as

9, forming charging pockets, H, in which,

the charge material, as J, is placed. The particular .object of the saidcenter plates, which are to be formed of material electricallynon-conductive, is to prevent acrossflo'w or shuntage of current fromone resistor to the other through the charge material; and the sainefunction is performed as to a longitudinal-passage of current by thetransverse plates. The bottom of the charge gallery, or of the pockets,is preferably downwardly sloped, as.l0, right} and left, from the centertoward the grating. The con densing elements are longitudinally disposedalong the outer vertical faces of the resistors and are parallelthereto.

When thecharge, composed of, say, ore, or a concentrate thereof, havingbeen suitably inixedwith a reagent, and also, if required, withadditional material for transforming the inert residual gangue to aliquid-- slag, has been supplied to the gallery or pockets thatconstitute charge receiving "means for serving and the tempera he chargeto the resistor e of the charge adey heat imparted by the quatelyincrease resistors, r fume and gases pass through the resistors es, asarrows a, and the h at the mom it. of uid or partially so, or an inertresidualseparatic-n to ash or sinter, or a combination of all ialls downalong the vertical faces of the re sister, or of the charge material, orin spaces Wren proceeds; metallic between them, until arrested by thesloped bottoms. The liquid, or even pasty slag -then flows into thelower interstices or the bottom of the resistors and from thence,through thespaces, as 12, of the gratinr s to the sumps, as denoted bythe arrows o, from whence it may be tapped off, as from the end"openings 13, 13*.

The particular advantages of the foregoing construction and operationare as follows, namely: The slag is being constantly evacuated from thezones of reaction, thereby neither clogging the resistors nor sealingthe charge-materials, which would prevent the tree evolution of fume andgas; the lower sides oi the resistors are eilectively utilized, becauseof their juxtaposition, to liquefy pasty slag and keep the slag-bathsuiiiciently hot and fluid to be readily tapped oil, and if any portionsof residue or charge-material in which the reaction has not beencompleted enters the sumps the exhaustion will be completed therein, theevolved fume and gas finding exit upwardly through the grate-spaces,into the resistors and thence to the condensers. Moreover, if azinc-lead ore is being smelted, the lead content, or a considerableportion thereof, is regainable in liquid form. In such instance, themethod and means here shown and described are favorable for such purposein that lead is producible at a relatively lower temperature than thatat which the free evolution of zinc-fume-takes place; consequently, atcertain distances away from the faces of the resistors, back into thecharge-material, where the temperature will be suificient only torelease and liquefy the lead, it will then percolate down along the faceof or through the char e and flow to the sump-baths wherein it wilprecipitate and be sealed from the direct radiated heat of theresistors.

Eachbf the fume-condensing elements is formed by a plurality ofvertically spaced plates disposed, as is here shown, in two series. Theinner series, those contiguous to the resistor, may beof compositeplates, that portion, as 14, in contact with the resistor, being ofmaterial elctrically non-coaductive, while the extension thereof, as 15,may be of carbon or graphite. These plates are set to form verticalspaces, as 16, into which flow the fume and gases after having passedthrough the resistor. The said plates rest upon bricks, or a tampedfacing, sloping downwardly, as 17, from the resistor, and a portion ofthe lower edges, as 18, of the 'p1at'es project over the inner edge, 19,of a zinc trough or receptacle, as 20. The outer series of spacedvertical plates, as 21, are set so that their centers, as lines 22, Fig.2,, shall coincide with the centers of the spaces, as lines Q3, formedby the inner series of plates, the edges of the two stacks abutting oneagainst the other. Thus, the two sets of spaces are vertically separatedor staggered. This separation may also be eii ected by lapping theplates, as shown in Fig. 3, or a longitudinal septum may be introduced.The result of the foregoing arrangement is that the spaces, 16, of theinner series of plates do not make direct connection with the spaces. asQ-t. oi" the outer series. The upper edges of the inner series of platesare covered with bricks, or tiles, as 25, 26. The bottoms ot the outerseries of plates rest in and are supported by the zinc reservoir, beingimmersed in the liquid metal, and a portion oil? their inner edges maybe cut away, as 27, coinciding with the overlying portions of the innerplates. ln this wise, a free space or chamber is formed, as i, boundedby the edges of the plates, one of the side-walls oi the reservoir andthe liquid metal beneath. The outer plates are stacked in a chamber, orgap, as 28, formed in the furnace and their upper ends may be flush withthe top of the furnace, as 29, or they may extend beyond it, asindicated in dotted outline, 30, or again they may be shortened, as 81,leaving an open space in which may be placed a layer of filter carbon orgraphite, or a layer composing heat insulating material such ascarborundum as flow down upon the zinc-bath,expand in.

the chamber 11 and thence, as arrows a, pass into the spaces of theouter plates and fiow upwardly, the residual gas passing to atmospheredirect as CO, or it may be burned to CO Any fume condensed in the spacesof the outerplates or in the overhead filter-carbon, if such is used,will fall into the reservoir, as arrows It is to be noted that as thelower ends of the outer series of plates are immersed in the Zincbath,their temperature will be correspondingly controlled thereat; but theupper ends of these plates, depending upon whether they are blanketedwith carbon, or flush with or extending beyond the top of the furnace,can be held to nearly any difierence of temperature desired, or asbetween that of the atmosphere and of the liquid zinc in. the reservoir.Furthermore, as has elsewhere been elaborated, the temperature of thezincbath may itself be readily controlled, asby a line, 33, in whichheat or air may be circulated.

Obviously, an additional expanding chamb may he provided at any desired.portion of the gap in which the outer plates are situated. So, too, anynumber of series of plates may be employed whereby the fume would becaused to travel up and down, crosswise,, or both, in various stacks ofspaces, ducts, or crevices, and the plates may be of such thicknessandbe so disposed as to virtually form laminated batteries. But anadvantage of controlling importance is derived from the arrangementshown in the drawings; for by employing stacks of verti cal plates withvertical spaces the outer series of plates may at any time be cleanedand by removing the cover-bricks, 25, 26, the same can also be done withthe inner series of plates, the dislodged matter being collected in thereservoir from whence it can readily be raked out through suitableendopenings, not shown.

The condensing system just described realizes to a unique degree one ofthe controlling requisites for the complete and rapid condensation offume to liquid metal, that is to say: progressive and controllablediminution of temperature from entry to exit; large area of rubbing ordiffusing surface;

low velocity of flow a'nda consequent minimum of deleteriousback-pressure at the reaction zone or zones.

g This'specification has purposely not been burdened with a detailedcitation of the various practical conditions pertaining .to igneouslyproduced oXi'd of zinc, Zinc blefide, oxidized and silicious ores, norto the various reagents, such ascarbon, copper and iron which may beutilized; and the foregoing brief reference thereto is simply to signifythat the several uses to which the present design of furnace may beadapted have had due consideration. l

It will doubtless be apparent that either of the longitudinal halves ofthe furnace, as

from the center line B, Fig. 1, may be operated as a unit; or that thecondensing ele ments may be transposed to the center and the resistorsto the outside thereof. However, there are distinct advantages incompounding the resistors and condensers after the manner shown in theaccompanying drawings such, say, as counterbalancing the emission ofheat and that one of the resistors and its component condensing elementmay be examined, repaired or renewed while the other set" are maintainedin operation. Therefore, it is tobe well understood that various shiftsand modifications may be made, as to which the applicant is fullycognizant, without evasion of the scope and dominant principles of theinvention herein disclosed.

- I claim as my invention:

1. An electric zinc furnace comprising a porous bed of carbon resistor,a means for serving charge-material to a vertical. face of saidresistor, 21 condensing system disposed along the other vertical face ofsaid resistor, a slotted or perforated grating upon which the saidresistor rests and an underlying sump which receives the non-volatilizedproducts of the reaction.

2. In an electric zinc furnace having a porous bed of carbon resistoralong a vertical face of which reacting material is served and whereatthe reaction takes place, a slotted or perforated hearth or grating uponwhich said resistor is stacked and an underlying sump adapted toreceive, from the bottom of the reaction zone, the inert or otherfiuidified products of the reaction.

3. In an electric Zinc furnace, a sump Ull= derlying'a slotted orperforated grating or hearth, upon which a porous bed of carbon resistoris supported, said sump being ar- Z reaction flow into the said sumpfrom one side of the resistor while any fume or gas thenafter producedin the said sump passes up into and thence laterally out of the saidresistor to the condensing system.

4. In an electric ZlIlC furnace, spaced resistors along whose opposingfaces the reaction is produced, the charging space or gap between theresistor being subdivided longitudinally by a wall, bricks, or slabsformed of electrically non-conductive material.

5. In an electric zinc furnace, parallel resistors along whose opposingvertical faces the reaction is produced, the charging space or gapbetween the resistor being subdivided longitudinally and transversely bywalls, bricks or slabs formed of material electrically non-conductive.

6. In an electric zinc furnace, a porous carbon resistor along one ofwhose vertical faces the reaction takes place, a stack of verticallyspaced plates contiguous to the other vertical face of said resistor. anouter stack of vertically spaced plates, each set being in staggeredrelation to the other, and an underlying receptacle for receiving liquidmetal, whereby the vaporized products of the reaction pass" into thespaces of the inner stack of plates horizontally, then deflectdownwardly to the reservoir and thence pass upwardly through the spacesof the, outer stack. I

7. In an electric zinc furnace, staggered stacks of vertically spacedplates constituting the condenser.

8. An electric furnace comprising vertically extending spaced condensingplates arranged in staggered relationship.

9. In an electric zinc furnace, stacks of vertically spaced plates,constituting the condenser, there being a barrier between the spaces inone stack and the spaces in the other stack.

10. In an electric zinc furnace, stacks of vertically spaced condensingplates, the spaces in one stack vertically separated from the other, thelower ends of one stack resting in a bath of liquid metal While theupper ends of the said stack at least extend nearly to the top of thefurnace. v

11. In an electric zinc furnace stacks of vertically spaced condensingplates, the spaces in one stack vertically separated from the other,portions of the lower "edges or" which lie above a bath of liquid metal,thereby forming a free space or chamber into which the fume and gas flowfrom one stack enters and thence passes into the spaces of anotherstack.

12. in an electric zinc furnace, stacks of vertically spaced condensingplates, the spaces in one stack vertically separated from the othen onestack at least reaching nearly to the top of the furnace and anotherstack being covered with tiles or bricks.

13. in an electric zinc furnace, stacks of vertically spaced condensingplates, the spaces in the stacks being vertically separated from eachother, the arrangement and construction being such that all of thespaces may he examined and cleanedfrom above, the dislodged materialbeing collected in an underlying reservoir.

14-. ln an electric zinc furnace, stacks of vertically spaced condensingplates, po of .one stack contiguous to a resistor being formed ofelectrically non-conductive material,

15, ln an electric zinc furnace, parallel porous resistors embracing aplurality of charge receiving means, the reaction taking place along theopposing vertical faces of said resistors which rest upon slotted orperforated hearths, sumps beneath the said hear-the for receiving liquidresidue "from the bottoms of the reaction zones, condensing; systems,disposed along the outer parallel -laces of said resistors, saidcondensing systems comprising stacks of vertically spaced plates, spacesin one stack separated from another, the condensed fume l beingcollected in reservoirs beneath the stacks and the residual gasespassing vertically therefron i into spaces in the outer stacks andfinally" passing to the atmosphere.

an electric Zinc furnace, having vertically spaced condensed plates, thespaces furnace being pi in one stack being vertically separated from thespaces in the other stack, the furnace be ing constructed so'that thetemperature of the lower ends oian outer stack is controlled by a bathof liquid metal and so that the temperature of the upper ends of saidstack can be manually controlled.

l7. l'n an electric zinc furnace, an integral condensing system, aporous resistor resting upon a slotted or perforated hearth, a sumpbeneath the said hearth and charge receiving means opposite to a faceof'said resistor, the reaction taking place in a zone at and back fromthe vertical face thereof, whereby when a metal, such as lead, isliberated at a relatively loW temperature it may percolate down alongtheface or "through the ore-charge thence flowing; into the afore saidsump.

18. i-ln electric furnace comprising broken carbon resistor supported ona, r above an underlying sump, the ch receiving space having a supportinsurface which slopes toward the sump .vherebv lluidified products of thereaction will be caused to flow into the sump.

19. An electric furnace coinprisin of carbon which is located over a s:vided with :1 ch ing portionat one side of the rescue condensing systthe other side 0' sister, the sun losing arranged so if is communicationbetween it and (lensing system only by passing thr resistor. I

combined zincfurnaceand conde ser comprising a resistor, a sur p in); Mto receive i'luidiiied products oi the r ction which takes place oneside of resistor. a condensing; system arranged the other side of theresistor and a sump at the lower part of the condensing Systeinfor reeiviup: liquefied zinc resulting from the condensa tion of he zincforces This specification signed aiid witnessed this 12th day of l

